KR102732168B1 - Diagnostic tag for an industrial vehicle tag reader - Google Patents

Abstract

An industrial vehicle is disclosed including a tag reader, a reader module, and a diagnostic tag, wherein the diagnostic tag is coupled to the industrial truck within a read range of the tag reader. The reader module and the tag reader cooperate to identify the diagnostic tag and individual tags in a tag layout, wherein the reader module distinguishes between individual tags in the tag layout and the diagnostic tag, correlates tag data with the identified individual tags in the tag layout, correlates the operation of the tag reader with the identified diagnostic tag, and generates a missing tag signal if the diagnostic tag is not identified or the operation of the tag reader is not within specified operating parameters.

Description

DIAGNOSTIC TAG FOR AN INDUSTRIAL VEHICLE TAG READER

Cross-reference to related applications

This application claims the benefit of U.S. Provisional Patent Application No. 62/157,865, filed May 6, 2015, entitled "DIAGNOSTIC TAG FOR AN INDUSTRIAL VEHICLE TAG READER" and U.S. Provisional Patent Application No. 62/157,863, filed May 6, 2015, entitled "INDUSTRIAL VEHICLE FOR IDENTIFYING MALFUNCTIONING SEQUENCED TAG AND TAG LAYOUT FOR USE THEREWITH".

Technical field

The present disclosure relates to industrial vehicles, and more particularly to diagnosing faults in a radio frequency identification (RFID) system on an industrial vehicle.

According to one embodiment of the present disclosure, an industrial vehicle includes a tag reader, a reader module, and a diagnostic tag, wherein the diagnostic tag is coupled to the industrial truck within a reading range of the tag reader. The reader module and the tag reader cooperate to identify individual tags of the diagnostic tag and a tag layout, wherein the reader module distinguishes between individual tags of the tag layout and the diagnostic tag and individual tags of the tag layout, correlates tag data with the identified individual tags of the tag layout, correlates the operation of the tag reader with the identified diagnostic tag, and generates a missing tag signal if the diagnostic tag is not identified or the operation of the tag reader is not within specified operating parameters.

According to another embodiment of the present disclosure, a method for identifying a fault in an RFID system including a tag reader, a diagnostic tag, and a reader module includes the steps of initializing the tag reader and identifying the diagnostic tag and individual tags of a tag layout through collaboration between the tag reader and the reader module. The method further includes the steps of enabling the diagnostic tag, generating a missing tag signal if the diagnostic tag is not identified while being enabled or if an operation of the tag reader is not within a specified operating parameter, and disabling the diagnostic tag if an individual tag of the tag layout is identified.

The embodiments set forth in the drawings are illustrative and are not intended to limit the scope defined by the claims. The following detailed description of the exemplary embodiments can be understood when read in conjunction with the following drawings, in which similar structures are indicated by like reference numerals:
FIG. 1 is a drawing illustrating an industrial vehicle according to one embodiment of the present disclosure;
FIGS. 2 and 2A through 2C are drawings illustrating some embodiments of a spatial relationship between a tag reader and a diagnostic tag according to one or more embodiments illustrated and described herein;
FIG. 3 is a block diagram of an RFID system according to one or more embodiments illustrated and described herein;
FIG. 4 is a flow diagram illustrating a diagnostic routine according to one or more embodiments illustrated and described herein;
FIG. 5 is a diagram illustrating modulation waveforms according to one or more embodiments illustrated and described herein;
FIG. 6 is a flow diagram illustrating a diagnostic tag modulation routine according to one or more embodiments depicted and described herein;
FIG. 7A is a drawing illustrating an RFID reader according to one or more embodiments illustrated and described herein;
FIG. 7B is a diagram illustrating an RFID gate according to one or more embodiments illustrated and described herein;
FIG. 7C is a drawing illustrating an RFID entry reader according to one or more embodiments illustrated and described herein;
FIG. 8 is a schematic diagram of a reader module according to one embodiment of the present disclosure;
FIG. 9 is a block diagram of a diagnostic tag module according to one embodiment of the present disclosure; and
FIG. 10 is a block diagram of another embodiment of a diagnostic tag module according to one embodiment of the present disclosure.

FIG. 1 illustrates an industrial vehicle (10) in the form of a lift truck including conventional industrial vehicle hardware, such as a steering mechanism (15), storage and retrieval hardware (20), and a vehicle drive mechanism (25), the details of which are beyond the scope of the present disclosure and may be gleaned from prior and yet undeveloped teachings in the industrial vehicle literature, examples of which include U.S. Patent Nos. 6,135,694, RE37215, 7,017,689, 7,681,963, 8,131,422, and 8,718,860, each assigned to Crown Equipment Corporation.

An RFID system of an industrial vehicle (10) will typically include a reader module (35) and a tag reader (30). The tag reader (30) is configured to cooperate with the reader module (35) to identify at least one diagnostic tag (45) and one or more tags (5) of a tag layout (FIG. 2A) in an environment, such as a building, warehouse or industrial facility. It should be appreciated that the reader module (35) may be a separate device or part of the tag reader (30). The industrial vehicle (10) further includes a vehicle controller (40). For example, and not by way of limitation, the tag reader (30) is expected to respond to RFID tags located in the vicinity of the industrial vehicle (10). It is contemplated that the RFID tags may be exclusively or a combination of passive and active RFID tags. The specific configuration of the reader module (35), the tag reader (30), and the associated RFID tags (hereinafter, "tags") to which they respond are beyond the scope of the present disclosure and may be gleaned from prior and heretofore undeveloped teachings, examples of which include U.S. Pat. No. 8,193,903 B2, assigned to Crown Equipment Corporation, entitled "Associating a transmitter and a receiver in a supplemental remote control system for materials handling vehicles," and U.S. Pat. No. 6,049,745, assigned to FMC Corporation, entitled "Navigation System for Automatic Guided Vehicle."

The tag reader (30) includes one or more read antennas (33). Although two are shown in FIG. 1, it should be understood that any number of read antennas (33) may be contemplated. Each read antenna (33) is expected to read tags that are within a read range R (FIG. 2A) (i.e., the distance between the tag and the read antenna (33) such that the signal strength is sufficient for the reader module (30) to identify the tag) and generate a respective tag read signal when the tags are within the read range of the read antennas (33). If there are two or more read antennas (33), it is expected that the respective read ranges of the read antennas (33) may overlap or be mutually exclusive. If the read ranges of the read antennas (33) overlap, it is expected that the tag reader (30) and the reader module (35) be equipped to distinguish between the respective tag read signals from different read antennas (33) and to determine which respective tag read signals from which read antenna (33) are valid. In one embodiment, the validity of a tag read signal is determined based on a comparison of the signal strength of the tag read signal by each read antenna (33) with a valid read antenna (33) determined to have a stronger (i.e., larger) signal strength from the tag. In one embodiment, the validity of a tag read signal is determined based on which read antenna (33) generates the tag read signal first.

The industrial vehicle (10) also includes at least one diagnostic tag (45). In one embodiment, there is one diagnostic tag (45) within the read range for each read antenna (33) on the industrial vehicle (10). In one embodiment, there is one diagnostic tag (45) positioned on the industrial vehicle (10) so as to reside within the read range of all read antennas (33) on the industrial vehicle (10). The reader module (35) distinguishes between individual tags in the tag layout and the diagnostic tag (45) and individual tags in the tag layout. The reader module (35) correlates the identified individual tags in the tag layout with the tag data, and the operation of the tag reader (30) with the identified diagnostic tag (45).

Still referring to FIG. 1, it is envisioned that each diagnostic tag (45) includes a unique identification code that is the target of the tag read signal generated by the read antenna (33). It is envisioned that one or more of the unique identification codes of the diagnostic tags (45) used to identify each diagnostic tag (45) for the purpose of diagnosis of the tag readers (30) are stored in the memory of the reader module (30). It is also envisioned that the unique identification codes for each diagnostic tag (45) are stored in the memory of the reader module (35) at a location where the reader module (35) can quickly identify each diagnostic tag (45) and improve the processing speed of the diagnostic routine described in detail below. In particular, referring to FIG. 8, the Confidence Group (221) is a first group that corresponds to the unique identification codes for the diagnostic tags and is read from memory locations (200) of the reader memory (205) as illustrated. Individual tags in the tag layout correspond to data in a reset group (220), a default group (230), one or more aisle zone groups (210), and one or more function zone groups (215). Identifying the confidence tag and individual tags in the tag layout are tag read signals that correlate to memory locations (200).

Referring to FIGS. 1 and 2, a diagnostic tag (45) is coupled to an antenna frame (34) and transmits a diagnostic signal that is received by a read antenna (33) of a tag reader (30), which in turn is used to generate a tag read signal. The reader module (35) verifies that the diagnostic signal from the diagnostic tag (45) is received and is within normal operating parameters. Normal operating parameters include, but are not limited to, received signal strength, signal delay, waveform shape, etc. Exemplary signal strength measurements include, but are not limited to, about -45 dB to about -50 dB. In some embodiments, it may be desirable to have a signal strength measurement of about -30 dB. In all embodiments, the received signal strength of the diagnostic tag (45) is set to be greater than the signal noise of the RFID system, but less than the received signal strength of individual tags in the tag layout. As will be described in more detail below, this allows the tag reader (30) to identify tags in the tag layout when the diagnostic tag is active. That is, the diagnostic signal does not mask the transmission signals of individual tags in the tag layout.

Referring to FIG. 2a, in one embodiment, a tag reader (30) is positioned within a read range (R) of a tag (5) of a tag layout. The tag reader (30) is coupled to an industrial vehicle (10) in this embodiment, and the tag (5) is within an environment. Referring to FIG. 2b, in one embodiment, a diagnostic tag (45) is mounted on the industrial vehicle (10) within the read range (R). Referring to FIG. 2c, in one embodiment, the tag reader (30) may include a read antenna (33) and an antenna frame (34). The read antenna (33) and the diagnostic tag (45) are coupled to the antenna frame (34), and the antenna frame (34) is coupled to the industrial vehicle (10). In this embodiment, the diagnostic tag (45) is spatially coupled between the read antenna (33) and the antenna frame (34). Examples of mounting locations on an industrial vehicle (10) include, but are not limited to, the undercarriage, the body, the bumper, storage and retrieval hardware (20), and/or the protective cage.

Referring to FIG. 9, in one embodiment, the diagnostic tag (45) is a passive RFID tag including an antenna circuit (82) communicatively coupled to a data chip (83). The reader module (35) is coupled to the antenna circuit (82) and regulates power to the diagnostic tag (45) by applying power (direct current (DC) voltage) to the antenna circuit (82) such that the antenna circuit (82) will not receive electromagnetic radiation from the tag reader (30) and will not activate the data chip (83) or transmit a diagnostic signal. It is envisioned that the reader module (35) will apply power to the diagnostic tag (45) to disable the diagnostic tag (45), as will be described in more detail below, and will remove power from the diagnostic tag (45) to enable the diagnostic tag (45), thereby enabling the diagnostic tag (45) to behave as a passive RFID tag.

Referring to FIG. 10, in one embodiment, the diagnostic tag (45) is an active RFID tag including a data chip (83) communicatively coupled to an antenna circuit (82) and coupled to a power circuit (84). The power circuit (84) supplies power to the data chip (83) and the antenna circuit (82) such that the active RFID tag responds to the tag reader (33) by a diagnostic signal. The reader module (35) is coupled to the power circuit (84), such that the reader module (35) supplies power to the diagnostic tag (45) by applying power to the power circuit (84). Therefore, it is expected that the reader module (35) will apply power to the power circuit (84) of the diagnostic tag (45) to enable the diagnostic tag (45), and will remove power from the power circuit (84) of the diagnostic tag (45) to disable the diagnostic tag (45), as will be described in more detail below.

FIG. 3 is a block diagram of a RIFD system (80) having a diagnostic tag (45). The diagnostic system (80) includes a reader module (35), a tag reader (30), a power source (47), and a diagnostic tag (45). The power source (47) is coupled to the reader module (35) and the diagnostic tag (45), and the reader module (35) is coupled to the tag reader (30). The diagnostic system (80) can be active or inactive based on whether power is enabled or disabled to the diagnostic tag (45). In this manner, power to the diagnostic tag (45) can be regulated, as will be described in more detail below. The tag reader (30) is communicatively coupled to the diagnostic tag (45). For example, as described above, a diagnostic signal transmitted by the diagnostic tag (45) is received by the read antenna such that the tag reader (30) generates a tag read signal. Additionally, the tag reader (33) can transmit electromagnetic energy of a particular frequency to activate and power the antenna circuit of the passive RFID diagnostic tag (45). In one embodiment, the power source is coupled to the vehicle controller (40) (FIG. 1) instead of the reader module (35). In this configuration, the reader module (35) and the vehicle controller (40) cooperate to regulate power to the diagnostic tag (45). In one embodiment, the power source (47) is not present, and the reader module (35) powers the diagnostic tag using power provided to the reader module (35).

FIG. 4 illustrates a diagnostic tag adjustment routine (50) that utilizes a diagnostic tag to diagnose the operational status of a tag reader in an RFID system. The diagnostic tag adjustment routine (50) begins by initializing the tag reader (51). The diagnostic tag adjustment routine (50) then waits for confirmation that the tag reader has been initialized (52). It is anticipated that the confirmation may be provided by the reader module (30) (FIG. 1) or the tag readers (33) (FIG. 1). The next step is to transition the diagnostic routing (50) to active (53) or inactive (54). The decision on transitioning between active (53) and inactive (54) is described in detail below. The diagnostic tag adjustment routine (50) may transition between the active (53) state and the inactive (54) state as needed. If the diagnostic tag adjustment routine (50) is inactive (54), the diagnostic tag adjustment routine (50) does not find a fault in the RFID system and waits until it transitions to an active state (53). The diagnostic tag adjustment routine (50) may be inactive (54) due to a tag reader identifying tags in the tag layout or the industrial vehicle (10) is expected to be stationary. In the active state (53), the diagnostic tag transmits a diagnostic signal together with its unique identification code. The reader module finds a fault in the RFID system (55) as described below.

FIG. 5 illustrates four diagnostic modes (70) for the diagnostic tag: an always on mode (71), a smart mode (72), a smart control mode (73), and an always off mode (74). The four diagnostic modes (70) are waveforms of the transmission of the diagnostic signal and relate to whether the diagnostic tag is enabled or disabled. The waveform may not transition between enable and disable at regular intervals (square wave) as shown in FIG. 5, may be enabled for a duration, or may be disabled for a duration. In the always on mode (71), the reader module will enable or maintain power to the diagnostic tag so that the diagnostic tag transmits its diagnostic signal at regular intervals. In the always off mode (74), the reader module will disable or remove power from the diagnostic tag so that the diagnostic tag does not transmit its diagnostic signal.

In smart mode (72), the reader module will disable the diagnostic tag when it receives a tag read signal from the tag reader that is indicative of a non-diagnostic tag within the read range of the tag reader. In smart mode (72), when the tag reader receives a tag read signal from the tag reader that is indicative of another tag in the tag layout, the reader module will disable or remove power from the diagnostic tag for the read interval (75). It should be understood that the read interval (75) indicates the start of the interval and not the duration of the interval. Therefore, the read interval (75) can have as long a final duration as necessary until a non-diagnostic tag is no longer identified by the tag reader, or until a delay timer has elapsed as described later, or until a signal is received from a tag other than the diagnostic tag.

It is contemplated that power to the diagnostic tag may be throttled so that the diagnostic signal transmitted by the diagnostic tag does not interfere with the standard operation of the industrial vehicle and tag reader, or so as to conserve power. Specifically, the tag reader may be used by the industrial vehicle to identify one or more individual tags in a tag layout in an environment, such as a building. The transmitted diagnostic signal of the diagnostic tag may interfere with or mask signals transmitted from individual tags in the tag layout during operation. To prevent or at least reduce the possibility of masking signals from other tags, the reader module will disable or remove power from the diagnostic tag at periodic or regular intervals (76) to "listen for" other tags, as illustrated in the smart throttle mode (73). When the diagnostic tag is disabled, the reader module will attempt to identify other tags, or will wait for a tag read signal from the tag reader that indicates a tag that is not a diagnostic tag. The smart control mode (73) is expected to operate like the smart mode (72) where the diagnostic tag is disabled during the reading interval (75) in addition to the regular interval (76).

Figure 6 illustrates a diagnostic routine (60). The diagnostic routine (60) starts in an initialization state (63), initializes state machine variables, and starts a diagnostic tag adjustment routine (50) (Figure 3). Once the variables and tag readers are initialized, the diagnostic tag adjustment routine (50) is set to inactive (54). Once the variables are initialized, the diagnostic routine (60) transitions to one of three states: a standby state (65); an always-on state (61); or an always-off state (62). In the always-on state (61), the diagnostic tag is enabled (i.e., powered up) and the diagnostic tag adjustment routine (50) (Figure 4) is set to active (53) (Figure 4) and an always-on mode (71) (Figure 5). It is expected that the diagnostic routine (60) will remain in the always-on state (61) until a fault is identified or the industrial vehicle is stopped. If a fault is identified in the always-on state (61) with the RFID system, the diagnostic routine (60) will transition to the always-off state (62). In the always-off state (62), the diagnostic tag adjustment routine (50) transitions to the inactive state (54) (FIG. 4), the diagnostic tag is disabled (i.e., power is cut off from the diagnostic tag), and the diagnostic mode (70) transitions to the always-off mode (74) (FIG. 5). A missing tag signal is generated when the diagnostic routine (60) transitions to the always-off state (62) if it has not transitioned from the initialization state (63) to the always-off state (61). If the always-on state (61) or the always-off state (62) is not selected, the diagnostic routine (60) transitions to the standby state (65) to wait for a tag read signal.

A missing tag signal is generated when a fault is identified by the diagnostic routine (60). Faults include, but are not limited to, signal parity, attenuation, serial faults, tag reader failures, and other forms of system degradation or errors that may adversely affect system operation and performance of the RFID system. In other words, the reader module checks to see if a tag read signal is generated upon identification of the tag reader of the diagnostic tag and/or if the receipt of the diagnostic signal from the diagnostic tag is degraded, exhibits any signal parity or attenuation problems, or is otherwise outside of certain operating parameters. The operating parameters include, but are not limited to, the received signal strength of the received diagnostic signal, the signal delay between transmission of the received signal by the diagnostic tag and reception of the received signal by the tag reader, the waveform shape of the received signal, signal parity, signal attenuation, or a combination thereof.

A tag read signal generated by a tag reader that is not derived from a diagnostic tag indicates that the tag readers are within the read range of a tag in the tag layout and are identifying (64) that tag in the tag layout. When a tag is identified (64), the diagnostic tag is disabled, the diagnostic tag conditioning routine (50) is transitioned to inactive (54), and the diagnostic mode (70) is transitioned to the always-off mode (62). A delay timer may be used for a period of time (i.e., the delay time) after the tag read signal is generated to wait for another tag in the tag layout to be identified by the tag readers. It is anticipated that the delay timer may be started after the tag read signal generated by the tag readers has subsequently stopped due to a tag in the tag layout being outside the read range of the tag readers. That is, as the industrial vehicle moves within the read range of a tag in the tag layout, the tag readers generate a tag read signal for the duration that a tag in the tag layout is identified. However, when the industrial vehicle leaves the read range of a tag in the tag layout, the tag read signals stop or are no longer generated and a delay timer is started. The amount of time of the read interval (75) (Fig. 5) is expected to be limited by how many tag read signals are generated and the subsequent delay timer.

When the delay timer has elapsed, the diagnostic routine (60) will transition to a standby state (65) for the next tag read signal to be generated by the tag readers. In the standby state (65), the diagnostic tag is enabled, the diagnostic tag modulation routine (50) is transitioned to active (53), and the diagnostic mode (70) is set to smart modulation mode (73). In the standby state (65), the modulation timer is used for a certain amount of time (i.e., modulation time) to wait and see if a tag read signal is generated for a tag in the lag layout. Once a tag read signal is generated in the standby state (65), the diagnostic routine (60) transitions to the identification state (64). It is expected that the amount of time for the regular interval (76) (Fig. 5) is limited by how many read signals are generated and the subsequent delay timer. This is in the standby state (65) and the always-on state (61) where the reader module searches for faults in the RFID system through the use of the diagnostic tag.

If a tag read signal is not generated in the standby state (65) and the adjustment timer has elapsed, the diagnostic routine (60) transitions to a turn off diagnostics state (66). In the turn off diagnostics state (66), the diagnostic tag is disabled, the diagnostic tag adjustment routine (50) transitions to inactivity (54), the diagnostic mode (70) transitions to the smart mode (72) or smart adjustment mode (73) (FIG. 5) to search for a tag, and the adjustment timer is reset and started again. In the turn off diagnostics state (66), it is expected that the industrial vehicle is in a position where no tag is present in the tag layout or that something has changed in the system such that the diagnostic tag is the only tag for which a tag read signal is generated. The turn off diagnostics state (66) allows the tag reader and the reader module to identify external factors that could lead to a misidentification of a fault. If the adjustment timer has elapsed, the diagnostic routine (60) transitions to the standby state (65). When a tag read signal is generated for a tag in the tag layout during the diagnostic clear state (66), the diagnostic routine (60) transitions to the identification state (64).

If a fault is identified in the identify state (66), the standby state (65), or the diagnostic clear state (66), the diagnostic routine (60) transitions to the always-off state (62). In the always-off state (62) and the fault state (55) (FIG. 4), a missing tag signal is generated. For example, but not limited to, if the reader module identifies a fault in the received diagnostic signal, the generated tag read signal, or does not identify a diagnostic tag, the reader module stops the diagnostic routine (60) and generates the missing tag signal. Examples of faults include, but are not limited to, a serial communication degradation or error, a tag reader degradation or error, or a count threshold that the diagnostic tag waits to transmit its signal or the generated tag read signal being adjusted, or a delay timer being exceeded.

When a missing tag signal is generated, the vehicle controller (40) (FIG. 1) is expected to reduce the driving speed of the vehicle drive mechanism (25) (FIG. 1) to zero. In other words, when a missing tag signal is generated, the vehicle controller (40) is expected to stop the industrial vehicle (10). After stopping the industrial vehicle (10), the vehicle controller (40) may transition the vehicle drive mechanism (25) to neutral. To handle the fault condition, a user may be prompted to transition the vehicle drive mechanism (25) from neutral using the user interface. For example, rather than being a limitation, a user of the industrial vehicle (10) may need to manually control the industrial vehicle (10) as autonomous functionality is disabled while a missing tag signal is generated.

In one embodiment, the diagnostic routine (60) includes a toggle mode (68) and a service mode (67). The toggle mode (68) allows the diagnostic routine (60) to switch between the diagnostic tests between two or more read antennas, such that only one read antenna is enabled at a time. In other words, the diagnostic routine (60) looks for a fault with the first antenna, and then looks for a fault with the second antenna. For example, but not limited to, if the industrial vehicle includes two tag readers, each with its own diagnostic tag, the diagnostic routine (60) will look for and identify any problems by receiving the tag read signal and the diagnostic signal of the first tag reader while the second tag reader is disabled. Once the testing of the first tag reader is complete, the first tag reader is disabled and the second tag reader is enabled and tested. The toggle mode is expected to be used in the standby state (65) and the always-on state (61).

The service mode (67) allows the diagnostic routine (60) to go through its steps without generating a missing tag signal and causing a defect in the industrial vehicle. This can be advantageous when the industrial vehicle is being serviced so that the RFID system can be tested without causing a defect in the industrial vehicle. An indication can be given to the user interface that the diagnostic routine (60) has identified a defect without generating a missing tag signal.

It is contemplated that the embodiments described herein may be used with many RFID devices, and are not limited to industrial vehicles. For example, and not limited to, RFID devices include handheld RFID devices, RFID security systems, RFID entry readers, and the like. In one embodiment, referring to FIG. 7A, an RFID system (90) includes a diagnostic tag (45) and an RFID reader (91). The diagnostic tag (45) is coupled to the RFID reader (91) within a read range (R) of the antenna (33) of the RFID reader (91). A fault in the RFID system (90) may be indicated by a flashing light (95), an audible tone from a sound device (96), and/or disabling the RFID reader (91) until it is repaired, manufactured, or reset. In one embodiment, referring to FIG. 7B, an RFID system (90) includes one or more diagnostic tags (45), and one or more RFID gates (92). Each diagnostic tag (45) is coupled to an RFID gate (92) within a read range (R) of a respective antenna (33) of each RFID gate (92). A fault in the RFID system (90) may be indicated by one or more flashing lights (95), an audible tone from one or more sound devices (96), and/or by disabling the RFID gate (92) until it is repaired or manufactured or reset. In one embodiment, referring to FIG. 7C, the RFID system (90) includes a diagnostic tag (45) and an RFID entry reader (93). The diagnostic tag (45) is coupled to the RFID entry reader (93) within a read range (R) of the antenna (33) of the RFID entry reader (93). A fault in the RFID system (90) may be indicated by one or more flashing lights (95), an audible tone from a sound device (96), and/or by disabling the RFID entry reader (93) until it is repaired or manufactured or reset.

The present disclosure provides an apparatus and process for checking the operational status of an RFID system. The apparatus and process are used to check for faults including, but not limited to, signal parity, attenuation, cascading faults, tag reader faults, and other forms of system degradation or errors that may adversely affect the system operation and performance of the RFID system. A missing tag signal is generated when a fault is identified. A diagnostic tag is mounted within the signal range of an antenna of a tag reader and may be used to provide an end-to-end test of the RFID system. The diagnostic tag may be configured to operate in one of several modes such that the diagnostic tag does not interfere with the operation of the RFID system when identifying tags in the environment. The diagnostic routine may be used when tag readers no longer identify tags in a tag layout during routine operation to check the operation of the system while stopping an industrial vehicle upon an identified fault.

Although the subject matter of the present disclosure has been described in detail and with reference to specific embodiments, it should be noted that this should not be taken to imply that the various details disclosed herein are essential elements of the various embodiments described herein, even though specific embodiments are illustrated in each of the drawings accompanying this detailed description. Furthermore, it should be apparent that modifications and variations, including but not limited to the embodiments defined in the appended claims, are possible without departing from the scope of the present disclosure. More specifically, although certain aspects of the present disclosure are identified herein as preferred or particularly advantageous, the present disclosure is not necessarily limited to such aspects.

It should be noted that references in this specification to "at least one" component, element, etc., or "one or more" components, elements, etc. should not be used to create an inference that the alternative use of the singular form should be limited to a single component, element, etc.

It should be noted that the terms "substantially" and "about" may be used herein to indicate the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. These terms are also used herein to indicate the extent to which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter.

The phrase "communicatively coupled" means that the components can exchange data signals with each other, such as electrical signals through a conductive medium, electromagnetic signals through air, optical signals through an optical waveguide, etc.

Although the functions are illustrated and depicted as being performed in a particular order in the illustrated embodiments, it should be noted that the functions may be performed in a different order without departing from the scope of the present disclosure. It should also be noted that one or more functions may be omitted without departing from the scope of the embodiments described herein.

Although specific embodiments have been illustrated and described herein, it should be understood that various other changes and modifications may be made without departing from the spirit and scope of the claims. Furthermore, although various aspects of the claimed subject matter have been described herein, such aspects need not be utilized in combination. Therefore, it is intended that the appended claims cover all such changes and modifications that fall within the scope of the claimed subject matter.

Claims (28)

An industrial vehicle comprising a tag reader, a reader module and a diagnostic tag,
The above diagnostic tag is coupled to the industrial vehicle within the reading range of the tag reader;
The reader module and the tag reader are configured to collaborate to identify individual tags of the diagnostic tag and tag layout; and
The above reader module,
To distinguish between individual tags of the above tag layout and the above diagnostic tags,
To correlate the identified individual tags of the above tag layout with tag data,
To correlate the identified diagnostic tags with the actions of the tag reader;
To regulate power to said diagnostic tag so that said diagnostic tag is inactive during identification of individual tags of said tag layout, and
configured to generate a missing tag signal if the diagnostic tag is not identified or the operation of the tag reader is not within specified operating parameters;
An industrial vehicle, wherein the generation of the above missing tag signal causes the industrial vehicle to stop. In the first paragraph,
The above industrial vehicle comprises two or more diagnostic tags;
The above tag reader comprises two or more reading antennas;
Each read antenna has a read range;
Each individual diagnostic tag is within the reading range of an individual reading antenna;
Each read antenna is configured to generate a tag read signal when receiving a diagnostic signal transmitted by said individual diagnostic tag within its respective read range; and
The above reader module,
to distinguish between the readout antennas, and
An industrial vehicle, wherein one of the read antennas is configured to generate a missing tag signal if the tag read signal corresponding to the diagnostic tag within its respective read range or if the tag reader is not operating within specified operating parameters. In the second aspect, the industrial vehicle, wherein the reader module is configured to toggle between each of the read antennas so that only one read antenna is enabled at a time to identify whether the read antenna is not generating a tag read signal corresponding to the diagnostic tag within each read range or whether the tag reader is not operating within specified operating parameters. In the first paragraph,
The above diagnostic tag comprises a passive radio frequency identification (RFID) tag;
The above passive RFID tag includes an antenna circuit and a data chip; and
An industrial vehicle wherein the reader module is configured to regulate power to the diagnostic tag such that power is applied to the antenna circuit during identification of individual tags in the tag layout to disable the passive RFID tag. In the first paragraph,
The above diagnostic tag comprises an active radio frequency identification (RFID) tag;
The above active RFID tag includes an antenna circuit, a data chip, and a power circuit; and
An industrial vehicle wherein the reader module is configured to regulate power to the diagnostic tag such that power is removed from the power circuit during identification of individual tags in the tag layout to disable the active RFID tag. In the first paragraph,
The above operating parameters include a received signal strength of a received diagnostic signal, a signal delay between transmission of the diagnostic signal received by the diagnostic tag and reception of the diagnostic signal received by the tag reader, a waveform shape of the received diagnostic signal, signal parity, signal attenuation, or a combination thereof. A method for identifying a defect in an RFID system, wherein the RFID system includes an industrial vehicle including a tag reader, a diagnostic tag, and a reader module, and the method comprises:
Step of initializing the above tag reader;
A step of identifying individual tags of the diagnostic tag and the tag layout through collaboration between the tag reader and the reader module;
A step of enabling the above diagnostic tag;
A step of regulating power to the diagnostic tag so that the diagnostic tag does not interfere with identification of individual tags in the tag layout;
generating a missing tag signal if the diagnostic tag is not identified during enablement or if the operation of the tag reader is not within specified operating parameters; and
A method comprising the step of disabling said diagnostic tag when an individual tag of said tag layout is identified. In Article 7,
A step of generating a tag read signal for a duration of identification of an individual tag of the above tag layout;
a step of starting a delay timer when the generation of the above tag read signal is stopped; and
A method comprising the step of enabling the diagnostic tag after a delay time has elapsed. In Article 7,
A method comprising the step of stopping the industrial vehicle when a missing tag signal is generated. In Article 7,
A step of distinguishing between the above diagnostic tags and individual tags of the above tag layout; and
A method comprising the steps of correlating identified individual RFID tags of the tag layout with tag data and correlating the diagnostic tags with the operation of the tag reader. In Article 7,
A step of regulating power to the diagnostic tag in one of three diagnostic modes, including a smart mode, a smart adjustment mode and an always-off mode, so that the diagnostic tag does not interfere with the identification of individual tags in the tag layout; and
A method further comprising the step of disabling or removing power to the diagnostic tag so that the diagnostic tag does not transmit a diagnostic signal when the diagnostic tag is in the always-off mode. A method in accordance with claim 11, further comprising the step of regulating power to disable the diagnostic tag during a read interval when the tag reader receives a tag read signal indicative of another tag in the tag layout when in the smart mode. In the 11th paragraph, during the reading interval when the tag reader receives a tag reading signal indicating another tag in the tag layout, and
A method further comprising the step of disabling said diagnostic tag during additional periodic, regular intervals to detect said one or more tag read signals from said one or more other tags while in said smart modulation mode to prevent or reduce the possibility of masking said one or more tag read signals from said one or more other tags. In the seventh paragraph, the method is configured such that the tag reader identifies tags when the diagnostic tag is active, such that the received signal strength of the diagnostic signal of the diagnostic tag is set to be greater than the signal noise of the RFID system but lower than the received signal strength of the tag read signals of the individual tags of the tag layout, so that the diagnostic signal does not mask the tag read signals of the individual tags of the tag layout. A method in accordance with claim 7, further comprising the step of executing a diagnostic routine to identify a fault if the tag reader fails to generate a tag read signal in the diagnostic routine or if a diagnostic signal from the diagnostic tag is not within specified operating parameters. A method in accordance with claim 15, wherein the specified operating parameters include a received signal strength of the received diagnostic signal, a signal delay between transmission of the diagnostic signal received by the diagnostic tag and reception of the diagnostic signal received by the tag reader, a waveform shape of the received diagnostic signal, signal parity, signal attenuation, or a combination thereof. A method for identifying a defect in an RFID system of an industrial vehicle, the RFID system comprising a tag reader, a diagnostic tag and a reader module, the method comprising:
Step of initializing the above tag reader;
A step of identifying individual tags of the diagnostic tag and tag layout located on the industrial vehicle through collaboration between the tag reader and the reader module;
A step of enabling the above diagnostic tag;
A step of regulating power to the diagnostic tag so that the diagnostic tag does not interfere with identification of individual tags in the tag layout;
A step of disabling power to the diagnostic tag during a read interval when the tag reader receives a tag read signal indicative of another tag in the tag layout while the diagnostic tag is in smart mode;
A step of distinguishing between the above diagnostic tags and individual tags of the above tag layout; and
A method comprising the steps of correlating identified individual RFID tags of the tag layout with tag data and correlating the diagnostic tags with the operation of the tag reader. In Article 17,
A method comprising the step of generating a missing tag signal if the diagnostic tag is not identified during enablement or if the operation of the tag reader is not within specified operating parameters. In Article 17,
A step of generating a tag read signal for a duration of identification of an individual tag of the above tag layout;
a step of starting a delay timer when the generation of the above tag read signal is stopped; and
A method comprising the step of enabling the diagnostic tag after a delay time has elapsed. In Article 17,
A step of regulating power to the diagnostic tag in one of four diagnostic modes, including an always on mode, a smart mode, a smart adjustment mode and an always off mode, so that the diagnostic tag does not interfere with identification of individual tags in the tag layout;
A step of maintaining power to the diagnostic tag so as to transmit a diagnostic signal at regular intervals while the diagnostic tag is in the always-on mode; and
A method further comprising the step of disabling or removing power to the diagnostic tag so that the diagnostic tag does not transmit a diagnostic signal when the diagnostic tag is in the always-off mode. In Article 20,
A method comprising the step of disabling or removing power to the diagnostic tag during a read interval by the tag reader receiving a tag read signal indicative of another tag in the tag layout while in the smart mode. In Article 20,
During the read interval when the tag reader receives a tag read signal indicating another tag in the tag layout, and
A method further comprising the step of disabling or removing power to said diagnostic tag during additional periodic, regular intervals to detect said one or more tag read signals from said one or more other tags while in said smart modulation mode to prevent or reduce the possibility of masking said one or more tag read signals from said one or more other tags. A method for identifying a defect in an RFID system, the RFID system comprising a tag reader, a diagnostic tag and a reader module, the method comprising:
Step of initializing the above tag reader;
A step of identifying individual tags of the diagnostic tag and the tag layout through collaboration between the tag reader and the reader module;
A step of enabling the above diagnostic tag;
A step of regulating power to the diagnostic tag so that the diagnostic tag does not interfere with identification of individual tags in the tag layout;
A step of maintaining power to the diagnostic tag so as to transmit a diagnostic signal at regular intervals while the diagnostic tag is in an always-on mode;
A step of distinguishing between the above diagnostic tags and individual tags of the above tag layout;
A step of correlating identified individual RFID tags of the above tag layout with tag data and correlating the diagnostic tags with the operation of the tag reader; and
A method comprising the step of generating a missing tag signal if the diagnostic tag is not identified during enablement or if the operation of the tag reader is not within specified operating parameters. A method for identifying a defect in an RFID system, the RFID system comprising a tag reader, a diagnostic tag and a reader module, the method comprising:
Step of initializing the above tag reader;
A step of identifying individual tags of the diagnostic tag and the tag layout through collaboration between the tag reader and the reader module;
A step of enabling the above diagnostic tag;
A step of regulating power to the diagnostic tag so that the diagnostic tag does not interfere with identification of individual tags in the tag layout;
A step of maintaining power to the diagnostic tag so as to transmit a diagnostic signal at regular intervals while the diagnostic tag is in an always-on mode;
A step of distinguishing between the above diagnostic tags and individual tags of the above tag layout;
A step of correlating identified individual RFID tags of the above tag layout with tag data and correlating the diagnostic tags with the operation of the tag reader;
A step of generating a tag read signal for a duration of identification of an individual tag of the above tag layout;
a step of starting a delay timer when the generation of the above tag read signal is stopped; and
A method comprising the step of enabling the diagnostic tag after a delay time has elapsed. A method for identifying a defect in an RFID system, the RFID system comprising a tag reader, a diagnostic tag and a reader module, the method comprising:
Step of initializing the above tag reader;
A step of identifying individual tags of the diagnostic tag and the tag layout through collaboration between the tag reader and the reader module;
A step of enabling the above diagnostic tag;
A step of regulating power to the diagnostic tag so that the diagnostic tag does not interfere with identification of individual tags in the tag layout;
A step of maintaining power to the diagnostic tag so as to transmit a diagnostic signal at regular intervals while the diagnostic tag is in an always-on mode;
A step of distinguishing between the above diagnostic tags and individual tags of the above tag layout;
A step of correlating identified individual RFID tags of the above tag layout with tag data and correlating the diagnostic tags with the operation of the tag reader;
A step of regulating power to the diagnostic tag in one of four diagnostic modes including an always-on mode, a smart mode, a smart adjustment mode and an always-off mode so that the diagnostic tag does not interfere with the identification of individual tags in the tag layout; and
A method comprising the step of disabling or removing power to the diagnostic tag so that the diagnostic tag does not transmit a diagnostic signal when the diagnostic tag is in the always-off mode. In Article 25,
A method comprising the step of disabling or removing power to the diagnostic tag during a read interval when the tag reader receives a tag read signal indicative of another tag in the tag layout while the tag reader is in the smart mode. In Article 25,
During the read interval when the tag reader receives a tag read signal indicating another tag in the tag layout, and
A method further comprising the step of disabling or removing power to said diagnostic tag during additional periodic, regular intervals to detect said one or more tag read signals from said one or more other tags while in said smart modulation mode to prevent or reduce the possibility of masking said one or more tag read signals from said one or more other tags. A method for identifying a defect in an RFID system, the RFID system comprising a tag reader, a diagnostic tag and a reader module, the method comprising:
Step of initializing the above tag reader;
A step of identifying individual tags of the diagnostic tag and the tag layout through collaboration between the tag reader and the reader module;
A step of enabling the above diagnostic tag;
A step of regulating power to the diagnostic tag so that the diagnostic tag does not interfere with identification of individual tags in the tag layout;
A step of disabling power to the diagnostic tag during a read interval when the tag reader receives a tag read signal indicative of another tag in the tag layout while the diagnostic tag is in smart mode;
A step of distinguishing between the above diagnostic tags and individual tags of the above tag layout; and
A method comprising the steps of correlating identified individual RFID tags of the tag layout with tag data and correlating the diagnostic tags with the operation of the tag reader.